Methylphenidate improves paediatric obstructive sleep apnoea

Methylphenidate improves paediatric obstructive sleep apnoea Methylphenidate is a dopamine norepinephrine reuptake inhibitor used in ADHD and narcolepsy. We report a case of a child with Wolfram syndrome who had narcolepsy and obstructive sleep apnoea. We used methylphenidate, which improved her narcolepsy as well as obstructive sleep apnoea. Case report We had earlier reported a case of a 10-year-old child with Wolfram syndrome with obsessivecompulsive disorder and narcolepsy.1 She was on insulin, telmisartan, spironolactone, desmopressin, and fluvoxamine. Her polysomnography showed an apnoea-hypopnea index (AHI) of 18.5, indicating severe obstructive sleep apnoea. Her snore index was 21.9, oxygen desaturation index was 10.1, baseline oxygen saturation was 97.4%, and the minimum oxygen saturation was 84%. An ENT evaluation did not reveal any adenoid or tonsillar hypertrophy or other abnormalities in the oropharynx. Her parents expressed reluctance towards non-invasive ventilation. We started her on methylphenidate 10mg primarily for narcolepsy. Her daytime sleepiness and respiratory distress reduced considerably. We performed a repeat polysomnography after two years. Her AHI index had reduced from 18.5 to 4.4, desaturation index reduced to 4.8, snore index became 1.4, baseline oxygen saturation improved to 98.3%, and minimum oxygen saturation increased to 86%. Discussion Obstructive sleep apnoea in Wolfram syndrome may be due to the incoordination of upper airway muscles arising from brainstem degeneration.2 Neuropathy due to diabetes may also aect the pharyngeal and genioglossal muscle tone, increasing the risk of sleep apnoea in this disorder.2 The normal decline of norepinephrine in sleep causes excessive loss of tone of genioglossus and pharyngeal muscles, resulting in sleep apnoea3 in these patients. Methylphenidate is known to reduce the reuptake of norepinephrine from the synapses, thus increasing its concentration.4 This increase in norepinephrine may increase the tone of the genioglossus and pharyngeal muscles during sleep, opening up the airway and reducing sleep apnoea. In addition to reducing the AHI index, the drug also improved oxygen saturation levels and reduced snoring events. Stimulants are used in obstructive sleep apnoea to reduce daytime sleepiness. Atomoxetine in combination with oxybutynin was found to reduce sleep apnoea severity in a clinical trial.5 This report shows that stimulants like methylphenidate may also help in improving obstructive sleep apnoea. This may be especially important in adults, where reduced tone of oropharyngeal muscles is the primary cause of sleep apnoea. Reference 1.Ravindren RK, Veettil RT, Athimannil S, Balaram N, Veedu PT, Veetil SA, Ayoor AK, Mathew S, Padinharath K, Balan S. Sequential presentation of obsessive-compulsive disorder and narcolepsy in a 10-year-old girl with Wolfram syndrome 1. The Journal of Nervous and Mental Disease. 2024 Jul 1;212(7):403-5. 2.Licis A, Davis G, Eisenstein SA, Lugar HM, Hershey T. Sleep disturbances in Wolfram syndrome. Orphanet Journal of Rare Diseases. 2019 Aug 2;14(1):188. 3.Fenik VB, Davies RO, Kubin L. REM sleep–like atonia of hypoglossal (XII) motoneurons is caused by loss of noradrenergic and serotonergic inputs. American journal of respiratory and critical care medicine. 2005 Nov 15;172(10):1322-30. 4.Challman TD, Lipsky JJ. Methylphenidate: its pharmacology and uses. In Mayo Clinic Proceedings 2000 Jul 1 (Vol. 75, No. 7, pp. 711-721). Elsevier. 5.Taranto-Montemurro L, Messineo L, Sands SA, Azarbarzin A, Marques M, Edwards BA, Eckert DJ, White DP, Wellman A. The combination of atomoxetine and oxybutynin greatly reduces obstructive sleep apnea severity. A randomized, placebo-controlled, double-blind crossover trial. American journal of respiratory and critical care medicine. 2019 May 15;199(10):1267-76. Funding None Potential conflict of Interest None